Compressed air and other pressurized gases have long been utilized to operate a variety of tools or other devices. Typically such gases have been routed through supply lines, often flexible lines, from a supply source to the device being operated. In the case of pneumatic tools, flexible reinforced rubber hoses often serve as the supply line to route compressed air from a compressor, supply tank or other air supply source to the tool being powered. The length of the supply line or lines being used may vary widely and generally no limit is imposed. In the case of a work environment such as a repair hanger for modern day aircraft, where a wide variety of rivet guns, drills, screwdrivers and the like are in use for the assembly or repair of very large aircraft, air supply lines may range up to 300 feet in length. Such lines are generally attached to a supply tank, which in turn is connected to a compressor. In such an environment, numerous supply lines would be attached to a corresponding number of connectors on the supply tank. The operating pressure carried by such lines may vary greatly, but it is common to utilize 100-150 psi.
When pneumatic supply lines are in use to power pneumatic tools, the supply lines necessarily have to be disconnected from their source of pressurized air from time to time. This may occur when the line is to be moved to a different air supply source in a different location or it may occur when the tool and line are to be taken out of service as at the end of a work shift. When such disconnection occurs, a certain amount of compressed air remains in the supply line. The female connector on the end of the supply line which attaches to a mating connector at the air supply source has historically provided one of two means to deal with this pent up air supply. In one instance the connector on the supply line would be a self sealing connector such as the well known variety of "quick-disconnect" couplings. In the other instance the connector would be an open connector which would allow the pent up compressed air to immediately vent. In the case of the self sealing connector, the pent up supply of compressed air in the supply line remains at essentially the same pressure as the original air supply source. This pent up air keeps the flexible supply line relatively rigid for a considerable period of time such that it cannot be easily rolled up for storage or for transport. This interferes with the progress of work. In addition, if it is desirable to quickly reconnect the supply line to a supply source, such as when a line is moved from one work location to another, the pent up air in the supply line creates back pressure making it more difficult to reconnect the line to a supply source which is under pressure. For these reasons it is more frequently the case that the connector on the supply line attaching to the air supply source is of the open type so that the lines are able to be immediately emptied of compressed air allowing them to be rolled up or otherwise more easily handled. It is the hazards that are encountered when the air supply line has an open connector that the present invention is intended to address. More specifically, when a supply line with an open type connector is to be disconnected from the supply source connector it is intentionally removed. The tool user may "kick" loose the supply line, by releasing the quick disconnect mechanism, because he or she has his or her hands full with the tool and other portions of the long and bulky line that is being disconnected. When the line is thus disconnected without the handler having his or her hands on the hose end, it will violently fishtail about as the pent up supply of compressed air immediately escapes through the open connector on the supply line. This results from the hose end experiencing a recoil force as the compressed air jets through the open hose connector. Numerous accident reports document serious injuries occurring to workers and bystanders as the result of such pneumatic line use.